IMAGING APPARATUS, COMPUTER PROGRAM, AND IMAGING CONTROL METHOD

Abstract

To provide a high-speed and optimum tilt control device by controlling both of a focus position and a tilt angle even when a scene changes in such a case where a subject changes.SOLUTION: To achieve the above object, an imaging apparatus according to an embodiment comprises: tilt control means that controls at least one of an imaging element and an imaging optical system and performs tilt controlling; focus lens drive means that drives a focus lens; and control means that has a plurality of control modes for performing focus correcting using at least one of the tilt control means and the focus lens drive means, and selects one of the plurality of control modes according to the number of subject areas within an imaging screen.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present invention relates to an imaging device capable of tilt control. [Background technology]

[0002] Conventionally, surveillance cameras are installed in high places such as ceilings, and the optical axis of the camera is directed diagonally downward to monitor people passing by on the road or to capture images of cars and their license plates. In this case, since the optical axis of the camera is directed diagonally downward, the focal plane on which the image is focused when capturing an image is a plane perpendicular to the optical axis, which often does not coincide with the imaging plane of the subject to be captured. As a result, the area that is in focus becomes part of the screen, and the other areas are out of focus. In response to such a problem, imaging devices that apply the Scheimpflug theorem are commonly known, which expand the depth of field range by controlling the relative tilt of a lens or an image sensor (hereinafter referred to as tilt control).

[0003] However, even if tilt control is performed at a constant angle from close to far subjects, there may be differences in the height of the subject's location or the height of the subject itself, and there may be multiple tilt angles that are in focus at close and far distances. Therefore, tilt control cannot be performed with a single tilt angle to keep subjects in focus from close to far distances. However, it is important for a surveillance camera to be able to recognize subjects from close to far distances. In addition, it is possible that the subject will change, and it will be necessary to perform appropriate tilt control depending on the situation. In that case, if only the tilt angle is controlled, it will be possible to focus on one subject among multiple subjects, but it will not be possible to focus on subjects in multiple areas. Therefore, it is necessary not only to change the tilt angle, but also to control the focus lens at the same time.

[0004] Patent Document 1 describes a technology in which focus information for multiple areas within a shooting area is obtained, and autofocus is performed using the focus information within a predetermined period of time, with tilt control and autofocus being performed at different times. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 11-242154 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the imaging device described in Patent Document 1 cannot simultaneously control the tilt control and the autofocus. Therefore, since the tilt control is performed in the same state after the focus is adjusted by the autofocus, it takes time to perform the autofocus and tilt control, and there is a problem that it is difficult to follow the changes in the subject in real time. SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide an imaging apparatus capable of optimizing focus lens drive and tilt control even when the subject changes, and capable of high-speed optimal tilt control. [Means for solving the problem]

[0007] In order to achieve the above object, an imaging device according to the present invention comprises: a tilt angle control means for performing tilt control for changing a tilt angle, which is an angle between the image sensor and a plane perpendicular to the optical axis of the imaging optical system, by tilting the image sensor; A focus lens driving means for driving the focus lens; a position information acquisition means for acquiring position information of a first area designated by a user on a captured image and position information of a second area designated by the user on the captured image; a defocus amount detection unit that detects a defocus amount in each of the first area and the second area; Position information of the first region, position information of the second region, and the defocus amount and calculating the tilt angle from a first calculation formula based on the position information of the first region, the position information of the second region, and the defocus amount from a second calculation formula based on the position information of the first region, the position information of the second region, and the defocus amount. A calculation unit for calculating a driving amount of the focus lens; By the swing angle control means, In advance The imaging device is tilted so as to achieve the calculated flapping angle, and the focus lens is driven by the focus lens driving means. In advance a control means for driving the focus lens by the calculated drive amount of the focus lens; the position information of the first region is a distance from a position corresponding to a perspective axis in the captured image to the first region, and the position information of the second region is a distance from a position corresponding to the perspective axis in the captured image to the second region, The first area is located above the position corresponding to the tilt axis in the captured image, and the second area is located below the position corresponding to the tilt axis. Effect of the Invention

[0008] According to the present invention, even when the subject changes, it is possible to optimize focus lens drive and tilt control, and obtain an imaging apparatus capable of high-speed optimal tilt control. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram showing an example of the configuration of an imaging device according to a first embodiment of the present invention. [Diagram 2] FIG. 1 is a diagram showing an example of a scene in which tilt control is performed. [Diagram 3] FIG. 13 is a diagram illustrating a tilt control method. [Figure 4] FIG. 13 is a diagram showing Example 1 in which a plurality of elevation angles exist. [Diagram 5] FIG. 13 is a diagram showing Example 2 in which a plurality of elevation angles exist. [Figure 6] FIG. 1 is a diagram showing an example of a shooting scene. [Figure 7] FIG. 11 is a diagram showing another example of a photographed scene. [Figure 8] 4A to 4C are diagrams illustrating focus lens drive and tilt control according to the first embodiment of the present invention. [Figure 9] 11A and 11B are diagrams for explaining focus lens drive and tilt control when there are three or more subjects. [Figure 10] FIG. 13 is a diagram showing an example of a typical plane to which the camera should be aligned when there is no subject. [Figure 11] 4 is a flowchart illustrating a plurality of control modes according to the first embodiment of the present invention. [Figure 12] FIG. 11 is a diagram showing an example of a photographed scene in the second embodiment. [Figure 13] 13 is a flowchart showing an example of a processing flow of the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. <Example 1> FIG. 1 is a block diagram showing the configuration of an image pickup apparatus according to a first embodiment of the present invention. The lens unit as the imaging optical system of this embodiment has a zoom lens 101 that moves in the optical axis direction to change the focal length, a focus lens 102 that moves in the optical axis direction to control the focus, and an aperture unit 103 that adjusts the amount of light. The imaging optical system in Fig. 1 shows one example, and some of the zoom lens 101, focus lens 102, and aperture unit 103 may be missing.

[0011] Light that has passed through the imaging optical system passes through a band pass filter (hereinafter, referred to as BPF) 104 and a color filter 105, and forms a subject image as an optical image on an imaging element . The BPF 104 may be movable forward and backward with respect to the optical path of the imaging optical system. The subject image is photoelectrically converted by the imaging element 106 to form an imaging signal. An analog imaging signal output from the imaging element 106 is gain-adjusted by an AGC (Auto Gain Control) 107 , converted into a digital signal by an AD converter 108 , and then input to a camera signal processing unit 109 .

[0012] The camera signal processor 109 performs various image processing (such as gamma conversion and white balance adjustment) on the digital imaging signal to generate a video signal. This video signal is displayed as an image on a display unit (not shown) to display the captured image. The video signal is outputted to a surveillance monitor device 111 via a network by wired or wireless communication through a communication unit 110. Furthermore, the communication unit 110 receives a command from an external control device such as an external PC and passes a control signal such as a command to a tilt / focus control unit 115 in the imaging device.

[0013] In this embodiment, a system including the surveillance monitor device 111 and the like is called an imaging device. Meanwhile, in Fig. 1, everything other than the surveillance monitor device 111 is housed in a single housing and constitutes a surveillance camera. A focus evaluation value calculation unit 112 receives RGB pixel values ​​and luminance values ​​from the AD converter 108 and the camera signal processing unit 109, and calculates a focus evaluation value to be used in tilt control and autofocus (hereinafter referred to as AF). For example, the shooting screen displayed on a display unit (not shown) of the surveillance monitor device 111 is divided into a plurality of subject regions, and the focus evaluation value is calculated based on the contrast and high frequency components of the image for each subject region. The focus evaluation value may be obtained by any method, such as a phase difference AF method or an infrared AF method, as long as it is an evaluation value that can be used for focus adjustment.

[0014] Incidentally, a display unit (not shown) for displaying the photographed screen may be selectively connected to, for example, the output side of the camera signal processing unit 109 so that the photographed screen can be monitored also on the surveillance camera side. The subject determination unit 113 performs image recognition on the video signal from the camera signal processing unit 109 and detects a specific subject from within the shooting screen. The specific subject may be a subject (e.g., a person, a face, a car, etc.) arbitrarily designated by the user or set in advance as a default, but is not limited to these examples.

[0015] The tilt / focus lens driving amount calculation unit 114 receives the focus evaluation value from the focus evaluation value calculation unit 112 and the subject recognition result from the subject determination unit 113. It also calculates an optimal tilt angle and focus position according to the scene using the focus evaluation value, the subject recognition result, and tilt angle information and focus position information from the tilt / focus control unit 115. The calculated tilt angle and focus position are transmitted to the tilt / focus control unit 115, and the tilt angle and focus position are controlled.

[0016] The tilt / focus control unit 115 has a built-in CPU as a computer, and executes various operations of the entire apparatus as a control means based on a computer program stored in a memory (not shown). The tilt / focus control unit 115 drives a focus lens in AF or manual focus (hereinafter, MF) based on an instruction from an external control device such as an external PC via the communication unit 110. It also receives current lens position information from the image sensor drive unit 116 and the focus drive unit 117, and transmits the current position to the tilt / focus lens drive amount calculation unit 114. It also controls the image sensor drive unit 116 and the focus drive unit 117 to send and drive the tilt angle and focus position calculated by the tilt / focus lens drive amount calculation unit 114.

[0017] The imaging element drive unit 116 functions as a tilt control unit (tilt angle control unit) and tilts the imaging element 106 based on the tilt angle instructed by the tilt / focus control unit 115. That is, the imaging element 106 is tilted to change the tilt angle, which is the angle between the imaging element 106 and a plane perpendicular to the optical axis of the imaging optical system. In this embodiment, the rotation axis for tilting the image sensor 106 is a horizontal axis (along the longitudinal direction of the image sensor) passing through the center of the shooting screen, and the image sensor 106 is tilt-controlled relative to the imaging optical system around this rotation axis.

[0018] In order to perform tilt control, a part of a lens in the imaging optical system may be tilt-controlled relatively to the imaging element, rather than the imaging element. A focus driver 117 controls the position of the focus lens 102 based on the focus setting position instructed by the tilt / focus controller 115 . As an example of a scene in which tilt control is performed, a scene as shown in Fig. 2 is assumed. Fig. 2 is a diagram showing an example of a scene in which tilt control is performed.

[0019] This is the case when there are subjects at close and far distances. If you focus using AF or MF without tilt control, you will end up focusing on either the close or far subject. On the other hand, Fig. 3 is a diagram explaining a tilt control method, and tilt control is a control for making a focused surface parallel to a horizontal surface such as the ground by tilting the image sensor 106 as shown in Fig. 3. As a result, subjects from close to far away can be included within the depth of field with respect to the surface parallel to the ground, and a focused state can be maintained. According to Scheimpflug's theorem, the elevation angle b is calculated using the following formula (1).

[0020] b = arctan(f / (Ltanα)) (Eq. 1) Here, f is the focal length, L is the subject distance, and α is the angle between the optical axis and the focal plane.

[0021] FIG. 4 and FIG. 5 are diagrams showing examples 1 and 2 in which there are a plurality of optimal swing angles. When the height of the surface on which the subject walks changes as in FIG. 4, or when there are a plurality of subjects with different heights as in FIG. 5, the optimal swing angle differs for each subject. Similarly, when the subject at the center of the shooting screen of the image sensor through which the swing rotation axis of the image sensor 106 passes is not in focus by AF or MF, the optimal swing angle differs for each subject. In other words, there are a plurality of optimal swing angles depending on the subject within the shooting screen. FIG. 6 and FIG. 7 are diagrams showing examples of shooting scenes, respectively, but when there are a plurality of subjects with different heights at different distances as in FIG. 6 and FIG. 7, the focus may not be achieved.

[0022] Furthermore, when each subject moves or disappears over time, the change in scene may cause the subject to lose focus using the previous tilt control. Furthermore, when there are multiple subjects at different heights, optimal control is often not possible using tilt control alone. An example of this will be described with reference to Fig. 8. Fig. 8 is a diagram for explaining focus lens drive and tilt control.

[0023] Assume that there are a person 801 (first area) and a vehicle 802 (second area) in the screen as the target subjects. The current tilt angle and the position of the focus lens 102 are as shown in the positional relationship at the top of FIG. 8. x is the amount of focus correction (defocus amount) from the imaging plane of the imaging optical system required to focus on the person 801. Also, y is the amount of focus correction (defocus amount) from the imaging plane of the imaging optical system required to focus on the vehicle 802. It is often difficult to focus on both the person 801 and the vehicle 802 by tilt control alone.

[0024] Therefore, in this embodiment, both focus correction by the focus lens and focus correction by tilt control are performed. An example of a method for calculating the driving amount for each in this case will be described. As shown in the upper part of FIG. 8, the distance (image height) from the tilt axis passing through the center of the imaging surface of the image sensor 106 to the subject is k1 [um] for the subject person 801 and k2 [um] for the subject car 802. Here, k1 and k2 correspond to the position information of the first area of ​​the shooting screen and the position information of the second area of ​​the shooting screen, respectively. Also, the focus correction amount on the imaging surface due to the movement of the focus lens 102 is β.

[0025] An example of calculating β is to calculate it from the product of the sensitivity of the focus lens 102 and the driving amount of the focus lens 102. On the other hand, the focus correction amount due to the tilt angle is the product of α=tan θ and the distances k1 and k2 from the tilt axis to the subject, where θ is the tilt angle [°].

[0026] From the above, x=k1×α+β (Formula 2) y=k2×α-β (Formula 3) Solving the simultaneous equations gives us β=(k2×x-k1×y) / (k1+k2) (Equation 4) α=(x+y) / (k1+k2) (Eq. 5)

[0027] Therefore, the tilt angle θ is θ=arctan((x+y) / (k1+k2)) (Equation 6) In order to approximately calculate the drive amount of the focus lens (focus lens drive amount) γ, for example, γ=β / (sensitivity of the focus lens) can be used. In order to accurately calculate, a high-order equation or a polynomial corresponding to the sensitivity may be solved. It should be noted that various modifications and approximations are possible for the method of calculating the focus lens drive amount γ, and the calculation method may use such modifications and approximations.

[0028] Next, a case where there are three or more subjects will be described. Fig. 9 is a diagram for explaining focus lens drive and tilt control when there are three or more subjects. When there are subjects ranging from close to far away as in Fig. 9, it is not possible to focus on all of the subjects using only tilt control and focus lens drive. The focus correction amounts (amount of deviation, amount of blur) from the imaging plane of the imaging optical system for a long-distance subject 901, a subject 902, and a close-distance subject 903 are a [um], b [um], and c [um], respectively.

[0029] An example of a control method in this case will be described. First, the first method is a method of controlling so that the maximum value of focus correction amounts such as a[um], b[um], and c[um] is minimized. Focus lens driving and tilt control are performed to control so that the maximum value of a[um], b[um], and c[um] is minimized. With this method, it is possible to minimize the blur of the subject in a scene such as that shown in FIG. 9. The second method is a method of calculating the amount that is determined to be in focus (allowable), that is, the depth of field, and controlling so that the focus correction amounts such as a[um], b[um], and c[um] are within the depth of field.

[0030] The depth of field is a value determined by the cell pitch per pixel and the aperture value of the image sensor 106. If the depth of field is FΔ, it can be calculated by solving the following equation. FΔ≧k1'×α+β (Equation 6) FΔ≧k2'×α+β (Equation 7) FΔ≧k3'×α-β (Equation 8)

[0031] The above formulas 6 to 8 are solved to calculate α and β, and the tilt angle θ and the focus lens drive amount γ are then calculated from α and β. If a[um], b[um], and c[um] are within the depth of field, the user will not notice the blurred focus, and there is no need to minimize the maximum values ​​of a[um], b[um], and c[um] as in the first method. If control is performed using the second method and the subject to be photographed does not fall within the depth of field, control using the first method can also be considered.

[0032] Generally, the depth of field for tilt control is deeper on the far side than on the near side, so it is effective to perform tilt control or focus lens drive with priority given to a close subject. For this purpose, a distance measuring means is provided to measure the distance to the subject, the distances to multiple subjects are measured, and tilt control or focus lens drive is performed with priority given to the subject relatively closer to the imaging element. Also, when the subject changes, it may disappear. In that case, the focus may be set on a flat surface such as the ground. In addition, there may be cases where the subject moves away from the plane on which you want to focus, so a method of controlling the position and tilt angle of a fixed focus lens may be considered.

[0033] FIG. 10 is a diagram showing a typical example of a plane to be aligned when there is no subject. As shown in FIG. 10, depending on the scene in which the camera is installed and the main subject, it is possible to set the plane to be aligned, for example, to a plane moved 1.6 m above the ground in parallel. By controlling to match the plane, the proportion of the in-focus part in the screen can be increased. Or, it is possible to prevent the image from being significantly blurred. The plane to be focused on may be determined by the user or may be a predetermined plane. In addition, a method of reading out the history of the positions and elevation angles of the focus lens that have been frequently stopped in the past from a memory (not shown), weighting them, and setting them to realize the focus lens drive to an effective plane according to the scene is also conceivable.

[0034] Next, an example of selection of a plurality of control modes according to the first embodiment will be described with reference to the flowchart of FIG. In this embodiment, there are a plurality of control modes for performing focus correction using at least one of the tilt control means and the focus lens driving means, and one of the plurality of control modes is selected according to the number of subject areas in the photographic screen. In S1101, a scan is performed. Scanning is a control for driving the focus lens 102 or the tilt angle of the image sensor 106 to gradually change in one direction. In S1102, during the scan, the focus evaluation value calculation unit 112 calculates an evaluation value for each of multiple regions on the screen.

[0035] In S1103, the subject determination unit 113 determines an area where a subject is present. The area where a subject is present is an area with a high evaluation value for each area calculated in S1102, or an area determined to contain a notable subject such as a person or a car by subject determination based on image recognition. In S1104, the number of areas where the subject is present (the number of subject areas) is determined. If it is determined in S1104 that there is one, in S1105, a first control mode is selected in which focus correction is performed using either tilt control or focus lens drive so that the area where the subject is present is brought into focus.

[0036] Specifically, for example, when the subject is not located near the center of the screen, focus correction is performed by tilt control. That is, when the distance (image height) of the subject from the center of the screen is greater than a predetermined value, tilt control is performed, and when the distance (image height) of the subject from the center of the screen is less than the predetermined value, focus correction is performed by driving the focus lens. If the number of areas where the subject is present is two in S1104, the second control mode is selected in S1106. That is, focus correction is performed using both tilt control and focus lens drive. Specifically, for example, the amount of focus correction for the area where the subject is present is calculated using Equations 2 to 5, as described above, so that the area where the subject is present is in focus.

[0037] That is, using the evaluation value for each region calculated in S1102, the position of the focus lens where the evaluation value for each region reaches its peak value is obtained as, for example, x and y in Equations 2 and 3. Based on the position of the region within the screen, k1 and k2 are obtained in Equations 2 and 3. Furthermore, the tilt angle θ and the focus lens drive amount γ are calculated using Equations 4 and 5. Then, the tilt control and the focus lens drive are performed so as to obtain the above-mentioned tilt angle θ and focus lens drive amount γ. In addition, the calculation of the focus correction amount for each region is not limited to the method described above, and the subject distance may also be obtained using a so-called image plane phase difference method that uses an external measurement sensor or an image sensor composed of multiple photoelectric conversion units in which each pixel has parallax.

[0038] If it is determined in S1104 above that the number of areas where the subject is present is three or more, the second control mode is selected in S1107, as in S1106. That is, focus correction is performed using both the tilt control and the focus lens drive. However, although the same second control mode is selected, the specific calculation method (calculation algorithm) is different from S1106. As described above, the tilt angle θ and the focus lens drive amount γ are calculated using, for example, equations 6 to 8 so that the maximum value of the focus correction amount (blurring amount) of the area where the subject is present is minimized. Then, tilt control and focus lens drive are performed so that the calculated tilt angle θ and focus lens drive amount γ are obtained.

[0039] In this case, the area where the subject is present is controlled so that it falls within the allowable circle of confusion diameter. In this embodiment, if the number of areas where the subject is present is equal to or greater than a predetermined number, the process proceeds to step S1107, and the predetermined number is set to 3, but the predetermined number may be, for example, 4 or more. In that case, if the number of areas where the subject is present is 2 or 3, the process proceeds to step S1106. Also, if the number of areas where the subject is present is 2 or more, the process may proceed to step S1107, and step S1106 may not be used.

[0040] In the above S1104, if there is no area where the subject is present, that is, if it is determined that the subject does not exist within the screen, a third control mode is selected in S1108, which controls to achieve a preset focus correction amount. That is, the focus lens drive position and tilt angle are returned to the past immediately before the start of control such as scanning. Alternatively, the position where the focus lens was most frequently stopped in the past focus lens drive and tilt control may be stored, and the focus lens drive and tilt control may be performed with the most frequently stopped position as the default. That is, the history of the past focus lens drive positions and tilt angles and the past focus correction amounts are stored in a memory (not shown), and the focus position and tilt angle are controlled based on the history information.

[0041] Even when there is no change in the area of ​​the subject, the same control may be performed as when there is no area containing a subject. As described above, in the first embodiment, the number of subject areas in the shooting screen is automatically determined by S1103. Then, according to the number, one of a plurality of control modes for focus correction using at least one of a tilt control means and a focus lens driving means is selected. Therefore, the focus does not shift due to changes in the subject, and optimal tilt control and focus lens driving according to the situation can be realized. <Example 2>

[0042] Next, a second embodiment of the present invention will be described with reference to Fig. 12. In the second embodiment, a user designates an arbitrary area of ​​a captured image and controls the focus position and the elevation angle. Fig. 12 is a diagram showing an example of a shooting scene in Example 2. The user specifies two areas of a subject A 1201 and a subject B 1202 shown in Fig. 12 using an area specification means (such as a touch panel or a mouse). In this example, the user sets the specified area by specifying the origin, corners, width, height, etc. of the area using the area specification means.

[0043] As a method for specifying a position, a width of a specified frame may be determined in advance, and the frame may be moved to an arbitrary position. For example, a first specified area 1203 is set by the above method, and then a second specified area 1204 is set in the same manner. Thus, instead of automatically determining the subject areas in the shooting screen in steps S1101 to S1103 in Fig. 11, the user may manually specify the subject areas in the shooting screen. In that case, the number of subject areas in the shooting screen specified by the user corresponds to the number of areas in which the subjects exist in step S1104. <Example 3>

[0044] In the second embodiment, after the user manually specifies the subject area within the shooting screen, the number of areas in which the subject is present is determined in step S1104. However, in the third embodiment, the flap angle and focus position are controlled without determining the number of areas. FIG. 13 is a flowchart showing an example of a processing flow according to the third embodiment. First, in S1301, as described above, the user arbitrarily sets two designated areas A (first area) (1203) and B (second area) (1204) as shown in Fig. 12. Here, designated area A is called evaluation frame A, and designated area B is called evaluation frame B.

[0045] Next, in S1302, k1 and k2 described in the first embodiment are obtained from the image heights of the two specified regions (evaluation frames). That is, the distance (image height) from the tilt axis passing through the center of the imaging surface of the image sensor 106 to the center of evaluation frame A is k1 [um], and the distance (image height) from the tilt axis passing through the center of the imaging surface of the image sensor 106 to the center of evaluation frame B is k2 [um]. That is, S1302 functions as a position information obtaining unit that obtains position information of the first region of the shooting screen and position information of the second region of the shooting screen.

[0046] Then, in S1303, the initial focus position is stored, and in S1304, the correction amount (defocus amount) x on the focal plane of evaluation frame A is calculated, and then, in S1305, the correction amount (defocus amount) y on the focal plane of evaluation frame B is calculated. That is, S1303 functions as a defocus amount detection means that detects the defocus amount in each of the first and second regions. The calculation method is as described in Example 1.

[0047] In S1306, the tilt angle θ and the focus correction amount β are calculated. As described in the first embodiment, the tilt angle θ is calculated from the formula 6 as follows: θ=arctan((x+y) / (k1+k2)) It can be calculated as follows. Based on the values ​​of the above calculation results, the swing angle and the focus position are controlled in S1307, thereby enabling swing control.

[0048] In the third embodiment, the case where there are two subjects has been shown, but by selecting an arbitrary subject from among a plurality of subjects, the user can focus on a subject that he or she wishes to focus on. In addition, when more than two areas or less than two areas are selected, which is not described in this embodiment, the processing can be performed in a similar manner to the processing for multiple focus positions described in the first embodiment. Furthermore, with regard to the setting of the designated area, although a rectangle has been described in this embodiment, any method and shape of designation may be used as long as the purpose of designating the area can be achieved.

[0049] In the above embodiments 1 to 3, the tilt angle of the imaging element is changed, but the tilt angle of the lens may be changed. Moreover, by controlling not only the horizontal tilt control but also the vertical tilt control in two axes in the same way, it becomes possible to realize the tilt control that maintains the recognizability of the subject in two planes. In the above first to third embodiments, examples have been described in which the calculation results are derived by performing calculations using the formulas in a CPU, etc. However, instead of calculations using the formulas, tables corresponding to these formulas may be stored in advance in a memory (not shown), and the same results as the calculation results based on the formulas may be directly derived using the tables.

[0050] Furthermore, the present invention is not limited to the above-described embodiment, and various modifications are possible based on the gist of the present invention, and these modifications are not excluded from the scope of the present invention. Also, a computer program that realizes part or all of the control in this embodiment as the functions of the above-mentioned embodiment may be supplied to the imaging device or imaging control device via a network or various storage media. Then, a computer (or a CPU, MPU, etc.) in the imaging device or imaging control device may read and execute the program. In this case, the program and the storage medium storing the program constitute the present invention. [Explanation of symbols]

[0051] 101 Zoom Lens 102 Focus Lens 103 Aperture unit 104 Bandpass Filter 105 Color Filter 106 Image sensor 107 AGC 108 AD converter 109 Camera signal processing unit 110 Communications Department 111 Surveillance monitoring device 112 Focus evaluation value calculation unit 113 Subject determination section 114 Tilt / focus lens drive amount calculation section 115 Tilt / Focus control section 116 Image sensor driver 117 Focus drive unit

Claims

1. a tilt angle control means for performing tilt control by tilting the image sensor to change a tilt angle between the image sensor and a plane perpendicular to the optical axis of the imaging optical system; A focus lens driving means for driving the focus lens; a position information acquisition means for acquiring position information of a first area designated by a user on a photographed image and position information of a second area designated by the user on the photographed image; a defocus amount detection unit that detects a defocus amount in each of the first region and the second region; a calculation means for calculating the flapping angle from a first calculation formula based on position information of the first region, position information of the second region, and the defocus amount, and for calculating a driving amount of the focus lens from a second calculation formula based on the position information of the first region, position information of the second region, and the defocus amount; a control means for tilting the image sensor by the tilt angle control means so as to achieve the tilt angle calculated in advance by the calculation means, and for driving the focus lens by the focus lens driving means by the drive amount of the focus lens calculated in advance by the calculation means, the position information of the first region is a distance from a position corresponding to a perspective axis in the captured image to the first region, and the position information of the second region is a distance from a position corresponding to the perspective axis in the captured image to the second region, an imaging device, characterized in that the first area is located above the position corresponding to the tilt axis in the captured image, and the second area is located below the position corresponding to the tilt axis.

2. When θ is the tilt angle, x is the defocus amount in the first area, y is the defocus amount in the second area, and k1 and k2 are the distances from the tilt axis passing through the center of the imaging surface to the first and second areas, respectively, the first calculation formula below is used. θ=arctan((x+y) / (k1+k2)) 2. The imaging apparatus according to claim 1, wherein the control means controls the tilt angle control means so as to satisfy the following:

3. When β is the driving amount of the focus lens, x is the defocus amount in the first area, y is the defocus amount in the second area, and k1 and k2 are the distances from the tilt axis passing through the center of the imaging surface to the first and second areas, respectively, the second calculation formula below is used. β=(k2×x−k1×y) / (k1+k2) 3. The imaging apparatus according to claim 1, wherein the control means controls the focus lens driving means so as to satisfy the following:

4. 2. The image pickup apparatus according to claim 1, wherein the control means stores an initial focus position of the focus lens before the defocus amount detection means detects the defocus amount.

5. 2. The imaging apparatus according to claim 1, wherein the tilt axis passes through a center of an imaging surface of the imaging element.

6. 2. The imaging device according to claim 1, wherein the positional information of the first area is a distance from a position corresponding to the tilt axis of the captured image to a center of the first area, and the positional information of the second area is a distance from a position corresponding to the tilt axis of the captured image to a center of the second area.

7. a position information acquiring step of acquiring position information of a first area designated by a user on a captured image and position information of a second area designated by the user on the captured image; a defocus amount detection step of detecting a defocus amount in each of the first region and the second region; a calculation step of calculating the flapping angle from a first calculation formula based on position information of the first region, position information of the second region, and the defocus amount, and calculating a driving amount of a focus lens from a second calculation formula based on the position information of the first region, position information of the second region, and the defocus amount; a tilt control step of tilting an image sensor so as to obtain a tilt angle calculated in advance by the calculation step, and a control step of driving a focus lens by a drive amount of the focus lens calculated in advance by the calculation step, the position information of the first region is a distance from a position corresponding to a perspective axis in the captured image to the first region, and the position information of the second region is a distance from a position corresponding to the perspective axis in the captured image to the second region, a first area being located above the position corresponding to the tilt axis in the captured image, and a second area being located below the position corresponding to the tilt axis,

8. A computer program for causing a computer to function as each of the means of the imaging device according to any one of claims 1 to 6.

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